Building elements – facade elements and facades: Field measurements of airborne sound insulation – Loudspeaker method using mls noise signals (NT ACOU 102)

  • Report #: NT ACOU 102
  • Approved: June 1999
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This NORDTEST method specifies a field method using a special kind of sound source signal, known as a “Maximum Length Sequence”. This is later referred to as the MLS method. It is used to determine the sound reduction index, as defined by IS0 140-5 of facade elements and facades. This method is an alternative to the loudspeaker method defined in IS0 140-5.